package com.emall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.common.to.es.SkuEsModel;
import com.emall.search.config.ElasticsearchConfig;
import com.emall.search.constant.esConstant;
import com.emall.search.service.MallSearchService;
import com.emall.search.vo.SearchParam;
import com.emall.search.vo.SearchResult;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.NestedQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author YuanShijia
 * @ClassName MallSearchServiceImpl.java
 * @Description
 * @createTime 2020年05月17日 15:59:00
 */
@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Autowired
    private RestHighLevelClient client;

    @Override
    public SearchResult search(SearchParam param) {

        // 准备检索请求
        //SearchRequest searchRequest = new SearchRequest();
        SearchResult result = null;
        SearchRequest searchRequest = buidSearchRequest(param);


        try {
            // 执行请求
            SearchResponse response = client.search(searchRequest, ElasticsearchConfig.COMMON_OPTIONS);


            result = buildSearchResult(response, param);

        } catch (IOException e) {
            e.printStackTrace();
        }


        return result;
    }

    private SearchResult buildSearchResult(SearchResponse response, SearchParam param) {

        SearchResult result = new SearchResult();

        SearchHits hits = response.getHits();

        List<SkuEsModel> esModels = new ArrayList<>();
        if (hits.getHits() != null && hits.getHits().length > 0){
            for (SearchHit hit : hits.getHits()) {
                String sourceAsString = hit.getSourceAsString();
                SkuEsModel sku = new SkuEsModel();
                SkuEsModel esModel = JSON.parseObject(sourceAsString, SkuEsModel.class);

                // 高亮
                if (!StringUtils.isEmpty(param.getKeyword())) {
                    HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
                    String string = skuTitle.getFragments()[0].string();
                    esModel.setSkuTitle(string);
                }

                esModels.add(esModel);
            }
        }
        result.setProducts(esModels);


        List<SearchResult.AttrVo> attrVos = new ArrayList<>();

        ParsedNested attr_agg = response.getAggregations().get("attr_agg");
        ParsedLongTerms attr_id_agg = attr_agg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attr_id_agg.getBuckets()) {
            SearchResult.AttrVo attrVo = new SearchResult.AttrVo();

            long attrId = bucket.getKeyAsNumber().longValue();
            String attrName = ((ParsedStringTerms) bucket.getAggregations().get("attr_name_agg")).getBuckets().get(0).getKeyAsString();
            List<String> attrValues = ((ParsedStringTerms) bucket.getAggregations().get("attr_value_agg")).getBuckets().stream().map(item -> {
                String keyAsString = ((Terms.Bucket) item).getKeyAsString();
                return keyAsString;
            }).collect(Collectors.toList());

            attrVo.setAttrId(attrId);
            attrVo.setAttrName(attrName);
            attrVo.setAttrValue(attrValues);

            attrVos.add(attrVo);
        }

        result.setAttrs(attrVos);



        List<SearchResult.BrandVo> brandVos = new ArrayList<>();
        ParsedLongTerms brand_agg = response.getAggregations().get("brand_agg");
        for (Terms.Bucket bucket : brand_agg.getBuckets()) {
            SearchResult.BrandVo brandVo = new SearchResult.BrandVo();

            long brandId = bucket.getKeyAsNumber().longValue();

            String brandName = ((ParsedStringTerms) bucket.getAggregations().get("brand_name_agg")).getBuckets().get(0).getKeyAsString();
            String brandImg = ((ParsedStringTerms) bucket.getAggregations().get("brand_img_agg")).getBuckets().get(0).getKeyAsString();
            brandVo.setBrandId(brandId);
            brandVo.setBrandName(brandName);
            brandVo.setBrandImg(brandImg);
            brandVos.add(brandVo);
        }

        result.setBrands(brandVos);


        ParsedLongTerms catalog_agg = response.getAggregations().get("catalog_agg");
        List<SearchResult.CatalogVo> catalogVos = new ArrayList<>();
        List<? extends Terms.Bucket> buckets = catalog_agg.getBuckets();
        for (Terms.Bucket bucket : buckets) {
            SearchResult.CatalogVo catalogVo = new SearchResult.CatalogVo();
            String keyAsString = bucket.getKeyAsString();
            catalogVo.setCatalogId(Long.parseLong(keyAsString));

            ParsedStringTerms catalog_name_agg = bucket.getAggregations().get("catalog_name_agg");
            String catalog_name = catalog_name_agg.getBuckets().get(0).getKeyAsString();
            catalogVo.setCatalogName(catalog_name);
            catalogVos.add(catalogVo);
        }
        result.setCatalogs(catalogVos);

        // 分页信息
        result.setPageNum(param.getPageNum());

        // 总记录数
        long total = hits.getTotalHits().value;
        result.setTotal(total);

        // 总页数
        int totalPages = (int) total % esConstant.PRODUCT_PAGESIZE == 0 ? (int) total / esConstant.PRODUCT_PAGESIZE : ((int) total / esConstant.PRODUCT_PAGESIZE + 1);
        result.setTotalPages(totalPages);

        return result;
    }

    /**
     * 准备检索请求
     * @return
     */
    private SearchRequest buidSearchRequest(SearchParam param) {

        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();

        // 1. bool query
        BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
        // 1.1 must 模糊匹配
        if (!StringUtils.isEmpty(param.getKeyword())){
            boolQuery.must(QueryBuilders.matchQuery("skuTitle", param.getKeyword()));
        }
        // 1.2 bool filter  按照三级分类ID查
        if (param.getCatalog3Id() != null){
            boolQuery.filter(QueryBuilders.termQuery("catalogId", param.getCatalog3Id()));
        }
        // 1.2 filter 品牌ID 查询
        if (param.getBrandId() != null && param.getBrandId().size() > 0){
            boolQuery.filter(QueryBuilders.termQuery("brandId", param.getBrandId()));
        }

        // 1.2 根据指定的属性查询
        if (param.getAttrs() != null && param.getAttrs().size() > 0){


            for (String attrStr : param.getAttrs()) {
                BoolQueryBuilder nestedBoolQuery = QueryBuilders.boolQuery();
                String[] s = attrStr.split("_");
                String attrId = s[0]; // 检索的属性ID
                String[] attrValues = s[1].split(":"); // 属性值
                nestedBoolQuery.must(QueryBuilders.termQuery("attrs.attrId", attrId));
                nestedBoolQuery.must(QueryBuilders.termQuery("attrs.attrValue", attrValues));
                // 每一个嵌入式查询
                NestedQueryBuilder nestedQuery = QueryBuilders.nestedQuery("attrs", nestedBoolQuery, ScoreMode.None);
                boolQuery.filter(nestedQuery);
            }
        }

        // 1.2 stock
        boolQuery.filter(QueryBuilders.termQuery("hasStock", param.getHasStock() == 1));
        // 1.2 价格区间
        if (!StringUtils.isEmpty(param.getSkuPrice())){
            RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("skuPrice");
            String[] s = param.getSkuPrice().split("_");
            if (s.length == 2){
                // 区间
                rangeQuery.gte(s[0]).lte(s[1]);
            }else if (s.length == 1){
                if (param.getSkuPrice().startsWith("_")){
                    rangeQuery.lte(s[0]);
                }
                if (param.getSkuPrice().endsWith("_")){
                    rangeQuery.gte(s[0]);
                }
            }
            boolQuery.filter(rangeQuery);
        }

        // 封装所有条件
        sourceBuilder.query(boolQuery);

        // 2. 排序，分页，高亮
        // 2.1 排序
        if (!StringUtils.isEmpty(param.getSort())){
            String sort = param.getSort();
            String[] s = sort.split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc")?SortOrder.ASC:SortOrder.DESC;
            sourceBuilder.sort(s[0], order);
        }
        // 2.2 分页

        sourceBuilder.from((param.getPageNum()-1) * esConstant.PRODUCT_PAGESIZE);
        sourceBuilder.size(esConstant.PRODUCT_PAGESIZE);

        // 2.3 高亮
        if (!StringUtils.isEmpty(param.getKeyword())){

            HighlightBuilder builder = new HighlightBuilder();
            builder.field("skuTitle");
            builder.preTags("<b style='color:red'>");
            builder.postTags("</b>");
            sourceBuilder.highlighter(builder);
        }

        // 3. 聚合分析
        // 3.1 品牌聚合
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg");
        brand_agg.field("brandId").size(30);

        // 3.1.1 品牌聚合子聚合
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg").field("brandName").size(1));
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg").field("brandImg").size(1));
        sourceBuilder.aggregation(brand_agg);

        // 3.2 分类聚合
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg").field("catalogId").size(2);
        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));
        sourceBuilder.aggregation(catalog_agg);


        // 属性聚合
        NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attr.attrValue").size(30));

        attr_agg.subAggregation(attr_id_agg);
        sourceBuilder.aggregation(attr_agg);


        String s = sourceBuilder.toString();
        System.out.println("构建的DSL" + s);
        SearchRequest searchRequest = new SearchRequest(new String[]{esConstant.PRODUCT_INDEX}, sourceBuilder);

        return searchRequest;
    }
}
